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 A128165 Numbers k such that k divides 1 plus the sum of the first k primes. 93
 1, 2, 6, 10, 20, 22, 28, 155, 488, 664, 992, 6162, 7840, 7975, 8793, 18961, 32422, 148220, 231625, 332198, 459121, 462932, 2115894, 8108930, 10336641, 11789731, 15500046, 23483195, 46571611, 48582404, 77033887, 105390951, 132421841, 229481560, 1224959312 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(44) > 4.4*10^10. - Robert Price, Dec 15 2013 a(50) > 10^14. - Bruce Garner, Jun 05 2021 LINKS Bruce Garner, Table of n, a(n) for n = 1..49 MATHEMATICA k = 0; s = 1; p = 2; A128165 = {}; While[k < 247336000, If[Mod[s += p, ++k] == 0, AppendTo[A128165, k]; Print[{k, p}]]; p = NextPrime@ p]; A128165 PROG (PARI) is(n)=sum(i=1, n, prime(i), 1)%n==0 \\ Charles R Greathouse IV, Nov 07 2014 (PARI) n=0; s=1; forprime(p=2, 1e9, s+=p; if(s%n++==0, print1(n", "))) \\ Charles R Greathouse IV, Nov 07 2014 CROSSREFS Cf. A085450 (smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n). Cf. A007504, A045345, A171399, A128165, A233523, A050247, A050248, A024450, A111441, A217599, A128166, A233862, A217600, A217601. Sequence in context: A028247 A209535 A065054 * A097646 A077084 A239542 Adjacent sequences:  A128162 A128163 A128164 * A128166 A128167 A128168 KEYWORD hard,nonn AUTHOR Alexander Adamchuk, Feb 22 2007 EXTENSIONS More terms from Ryan Propper, Apr 05 2007 a(34) from Robert G. Wilson v, Jan 21 2011 a(35) from Robert Price, Dec 15 2013 STATUS approved

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Last modified January 21 10:22 EST 2022. Contains 350476 sequences. (Running on oeis4.)